A series of hydrazones 5a–i were synthesized by the condensation of hydrazides derived from dichlorophenylacetic acids with different aromatic aldehydes and ketones. Their structures were confirmed by spectroscopic data and elemental analysis. Hydrazones 5a–i were evaluated for α‐glucosidase and urease inhibition activities. Five compounds exhibited potent α‐glucosidase inhibitory potential with IC50 values 8.5 ± 0.3, 22.2 ± 0.78, 32.9 ± 1.5, 34 ± 2.4, and 170.6 ± 7.5 μM, respectively, which are many times better than that of the standard inhibitor acarbose (IC50 = 840 ± 1.73 μM). Furthermore, molecular docking study was performed to explore the binding mode in the active sites of α‐glucosidase and urease enzymes. 相似文献
This research presents the applications of entropy generation phenomenon in incompressible flow of Jeffrey nanofluid in the presence of distinct thermal features. The novel aspects of various features, such as Joule heating, porous medium, dissipation features, and radiative mechanism are addressed. In order to improve thermal transportation systems based on nanomaterials, convective boundary conditions are introduced. The thermal viscoelastic nanofluid model is expressed in terms of differential equations. The problem is presented via nonlinear differential equations for which analytical expressions are obtained by using the homotopy analysis method (HAM). The accuracy of solution is ensured. The effective outcomes of all physical parameters associated with the flow model are carefully examined and underlined through various curves. The observations summarized from current analysis reveal that the presence of a permeability parameter offers resistance to the flow. A monotonic decrement in local Nusselt number is noted with Hartmann number and Prandtl number. Moreover, entropy generation and Bejan number increases with radiation parameter and fluid parameter. 相似文献
The solution rheology of poly(acrylonitrile-co-itaconic acid) (poly(AN-co-IA)) in 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) spanning dilute, semidilute unentangled and entangled regimes were investigated. The exponents in the specific viscosity ηsp ~ overlap parameter c[η] power law were 1, 2 and 4.7 for dilute, semidilute unentangled and entangled regimes, respectively, which were found to be consistent with the scaling prediction for neutral linear polymers in θ-solvent. For dilute solutions (lower than 0.9 wt.%), the linear viscoelastic responses were observed to be in good agreement with the Zimm model (Flory exponent ν = 0.5). While for semidilute unentangled solutions (between 0.9 and 8 wt.%), results obtained had been found to be consistent with Rouse model. Considering Flory exponent ν = 0.5 and the concentration dependences of the specific viscosity and relaxation time, it had been evaluated that poly(AN-co-IA) in [BMIM]Cl behaves as a neutral polymer in θ-solvent. It had also been suggested that according to the unusual deviation of Cox-Merz rule, poly(AN-co-IA)/[BMIM]Cl solutions are typical neutral polymeric liquids for the concentrated solutions but have shown a more complicated behavior at high deformation rates. 相似文献
Peristaltic pumping of Sisko fluid through the non-uniform asymmetric channel is addressed. Main motivations are given to nonlinear radiation and inclined magnetic field.
The perturbation technique and lubrication approach are utilized for development of governing problems and solutions. Resulting equations are solved for velocity, temperature, pressure and stream function. Trapping phenomenon is also observed. Variation of pertinent parameters is plotted and illustrated physically. The larger inclination of the magnetic field leads to a rise in velocity. Moreover, the size of trapping bolus tends to reduce and finally disappears for the larger fluid parameter. To our knowledge, such attempt for linear radiation and without inclined magnetic field does not exist even for both symmetric and asymmetric channels. Further it should be noted that problem remains nonlinear even after utilizing long wavelength and low Reynolds number assumptions.
In this paper, we examine the transmission of a probe field through a one dimensional photonic crystal (1DPC) when the sixth layer of the crystal is doped with four level atoms. We analyze effects of the external driving field on the passage of weak probe field across the photonic crystal. It is found that for the phase time delay of the probe photons, intensity of the driving field switches the Hartman effect from sub to superluminal character. It is interesting to note that in our model, the superluminal transmission of the probe pulse is accompanied by a negligibly small absorption of the incident beam. It ensures that the probe field does not attenuate while passing through the photonic crystal. A similar switching of the Hartman effect may be obtained by adjusting detuning of the probe field related to the excited states of the four-level doping atoms. 相似文献
We demonstrate tunable time-slot interchange of 40 Gbits/s optical data packets using a conversion-dispersion-based tunable optical delay element. Odd and even data packets are extracted from an input signal, delayed relative to one another in a highly dispersive medium, and then multiplexed back together. Tunability is demonstrated by operating with two different packet lengths, 182 and 288 bits/packet, and a bit error rate of <10(-9) is achieved. 相似文献
The hazard and inconvenience of storing and handling concentrated hydrogen peroxide can be avoided by using instead the solid complex which 1,4-diazabicyclo[2.2.2] octane forms with hydrogen peroxide, it reacts with trialkylchlorosilanes to give bis(trialkylsilyl) peroxides in good yield. 相似文献
Fumariflorine (, the only known alkaloidal -(β-dimethylaminoethyl)benzoic acid, has been isolated as its ethyl ester from Lam. (Fumariaceae). Since alkaloids – are also present in the plant, it is probable that the biogenetic sequence for the catabolism of the lactonic phthalideisoquinolines involves initial quatermination to an N-metho salt, Hofmann elimination, and oxidative cleavage of the resulting olefin to supply a substituted -(β-dimethylaminoethyl)benzoic acid. 相似文献
The radical-dependent oxidation of unsaturated fatty acids is a fundamental reaction in lipid chemistry, biochemistry, and technology. We report herein the first successful application of 1H–13C HMBC NMR experiment for the identification and quantification of complex and minor (3.9% to 0.85%) components of cis and trans primary hydroperoxide isomers of oxidized oleate and linoleate methyl esters in solution, without the need of laborious isolation of the individual components. 相似文献